Friction shock absorber for railway car trucks



Aug. 19, 1952 G. E. DATH 2,607,583 FRICTION SHOCK ABSORBER Fok RAILWAY CAR TRUCKS Filed Nov. 23, 1949 2 SHEETS-SHEET 1 1952 G. E. DATH 7 2,607,583

FRICTION SHOCK ABSORBER- FOR RAILWAY CAP TRUCKS Filgd Nqv. 23, 1949 0 1 2 SHEETS-SHEET 2 InVenlZr:

( e.b r g e 1117p? k.

Patented Aug. 19, 1952 Geor e. E- -'Da M al J al i r M nerrInc-rQ a mI oaeornorati n o iD l V ware ApplicatidIi November 23, 1949, Serial No. 128,995

invention relates to improvements in frictiori sh'o'ck absorbers for snubbingi or dampening the action of railway car truck springs.

One object of the invention is to provide a friction shock absorber of the characterindijcated; comprising a-friction casing, friction shoes idinglytelescoped within the casing, a spring ollower havingwedging engagement with the shoes, a spring within-thecasing yieldingly op- "'posing-inward'movement of thespring follower, and a'n additional springyieldingly opposing in- 01"thisspecificatiom-Figure 1 is a top plan-view i oi' myimprovedfriction shock 1 absorber; Figure 2' is 'a=--' transverse,- vertical sectional view, corre- "5% spending substantially to the a line 2 2 o'f'iFigspectively, of the spring follower and releasing "-5 plunger}- of my improved -=shockatabsorber. .Figure 5 is aiyi'ewsimilar to-Figure 2;!illustrating antherembodiment of the invention:- Figure 6 is a bottom plan view of-the spring? follower shown Figure 5.

Referring-first to the embodiment of the invenimproved- -friction -shock; :absorber'. comprises oadly a frictionacasing A, three frictionshoes B -B, a spring followerv Q'a" releasing plunger D; and-springs-E and F.

lhe casing A is inlthe form of a tubular member of hexagonal, transverse cross section, :open at -its upper endxandclosed, attits bottomlend by presents three lengthwise extending friction suraces: .H of Meshapedgtransverse cross section, "each ewshapedvsurface ll. being formedbytwo adjacentawalls ofthe hexagonal casing: At alternate corners of the-casing; the interior sidewalls are ;.vertically z'slottedz: at ,,their lower ends, as n'dicated; at l 2. 1: The transverse walls at, the upper ends of-zthes slots: I52 provide stop; shoulders or. lizfor 2a;purpose-hereinafter:pointed out.

,j, 2 The frictionshoes B are-three in nuinber and are arranged symmetrically about the, vertical central axis ofthe ,casing A, a in slidin engagement with thessidewalls of-=said .casing.; Each shoe Bcomprisesfan elongated, platelikasection M of V-shaped, transverse cross section, and. an

inwardly enlarged head I 5; at the rtop end oi the plate section M. The plate section lLpresents a-lengthwise -extending friction surface l6 -=o n its :outer -:side of -V-shaped transverse cross section -=aengaged with; one of-the V-shaped friction'surard 'm'ovement of the shoes only and acting to l orc'e the's'hoes outwardly away from the spring 7 faces of :the casing. At its. lower end, the -platef-likGfSBO'biOIl l4 of eachshoe B isprovided-with a :laterally outwardlyproj ecting stoplug H, which is; looatedat the corner: presented bylthe, angu- ;larly diverging portions of the V-shapedisu-r-face ofeach, shoe,- and is engaged in:- the correspond- -;ing slot- [lot-the casing-in baclooftheshoulder dent,- engagement of" the stop lug -l l of each shoe, with; the 1 corresponding shoulder-l 3 of the casing, positively limits outward movement of-said shoe.

The laterally inwardly projecting head--l,5 of

iunderneath side. "The wedge faces-=1 8--|'8-l8 of the three shoes divergedownwardly as clearly shown in Figure 2. Each shoe-has'an inwardly T projecting,- horizontal lip 1 or flange l 9 :1 on? the 1 inner side of its head, located abovethe wedge face of saidshoe, and said shoe is'cut out on its inner .side above said flangeas shown in- Figures 1 :Land 2; to'provide a: seat for the-usual ispring centering, projection :on the top follower- 'plate ion illustrated in"'-.Figures 1: to 4 inclusive, my

of a: cluster of railway car truck springs.i=- ;Each

shoe further has a laterally outwardly projecting, horizontal-flangeifl at its upper end overhanging the upper end of the casing A ande-eng'ageable therewith to; limit compression oflthe'mechanism a f .j'The' spring follower C is in the fornr'o'f airingr zlike block; having three upwardly converging-,ifiat uwedge facesl2 l.-'2 1 2!" at the upper side thereof, correspondingly inclined to" and engagediwithi the =-'-xwedgezfacesi l8-1-'- l8;-'l.8 of the three shoes;rTf='Ihe block G is provided withia'n axial bore: 22, :within which the plunger'D isloosely-slidable. i

a transverse wall l0; ZrTheinter-ior of the casing I "The plunger D is inithe form ofa solid'cylinder,

- .cprovided' with a peripheral flange: 23 i at its lower -ting the underneath ;-sides ,of ;the'- end;?:"Ihe plunger D is slidingly telescopedwithin thespring follower C'and has its topen'd abutifianges I 9l9-l9 of the three shoes. ;The springs E and F are, arranged within the casing A, between the shoes B B-;-B.g :Each of h er pri es is -thrdo m of ah c -qq -r the nrins Fte eh a i h nt e pring E nds rounding the latter. The inner spring E has its up; per end bearing on the bottom end of the plunger D and its lower end bearing on an upstanding hollow boss 24 on the wall In of the casing A. The outer spring F has its top end bearing on the bottom side of the follower rin C and its bottom end surrounding the boss 24 and bearing directly on the bottom wall 10 of the casing A. The,

springs E and F are preferably under a predetermined amount of initial compression in the as-' sembled condition of the mechanism. The hol-l low boss 24 on the bottom wall of the casing provides a seat which is adapted to accommodate the usual spring centering projection of the bottom spring follower plate of a cluster of truck springs.

My improved shock absorber preferably replaces one or more of the spring units of a truck spring cluster of a railway car, being interposed between the top and bottom sprin plates of said cluster. i

7 The operation of my improved shock absorber is as follows: Upon the spring cluster of the truck of a railway car being compressed between the spring follower plates of the cluster, the shoes B BB are forced downwardly with respect to the casing A against the spring resisted ring and the spring resisted plunger D.

j I Due towedging engagement between the spring follower ring C and the shoes B-B-B, the

latter are spread apart into tight frictional engagement with the friction surfaces of the casingA. Frictional resistance is thus provided between the shoesB-B-B and the casing A during sliding movement of the shoes. The

ffrictional resistance thus provided is augmented by the resistance afforded by the inner spring E, which directly opposes inward movement of the shoes through the medium ofthe interposed '7 plunger 'D. The desired resistance is thus proyided to properly snub the action of the truck springs.

Upon recoil of the truck springs and upward movement of the top spring follower plate of the truck spring cluster, the springs E and F return all of the parts to the normal full release positions shown in Figure 2, the inner spring E,

throughthe plunger D, acting directly on the shoes B'-BB to force the shoes away from the follower'ringC and break the contact between Y the engaging wedge faces of said shoes and follower ring, thereby assuring instantaneous release of the mechanism. Outward movement of the shoes is positively limited by engagement i of the lugs [1 thereof with the shoulders l3 of through 'the spring follower and has direct 'shouldered'engagement with the shoes.

Theimproved shock absorber, as shown in :fFigures'S and 6, comprises a friction casing G,

three friction shoes H-'-H-H, and a spring followerring J ,s'imilar to the casing A, the shoes IBBB,' and'the spring follower C, hereinbefore described, and operating in a similarmanner,

and springs K, L, and M. w Each spring K, L, and M is in the form of a helical coil, the spring K being'inner'most, the

spring L surrounding the spring K, and the spring M surrounding the spring L. The spring M has 7 seated on the boss I24 and its top endbuttressed against the follower ring J, said top end being engaged in an annular seat I25 in said ring. The spring K has its bottom end seated on the boss I24 and its upper end portion extending through the bore I22 of the rin J, with its top end engaged with the flanges or lips lIB-I l9- H9 of the shoes HH-I-I.

'The springs'K, L, and M are preferably under a predetermined amount of initial compression in the assembled condition of the mechanism, the inner spring K acting directly on the shoes to oppose movement of the same inwardly of the casing, and force said shoes away from the ring J to break the contact between the engaging wedge faces of said shoes and the follower ring J in the releasing action of the mechanism.

I claim:

1. In a friction shock absorber, the combination with a friction casing; of a pluralityof friction shoes slidingly telescoped within the .casing; a spring follower having wedge faces in wedging engagement with the shoes, said spring follower having an opening therethrough; and inner and outer yielding means within said casing, said outer yielding means being buttressed against said spring follower to yieldingly oppose inward movement of the latter, said inner yielding means having a portion thereof extending through the opening of said spring follower and into engagement with said shoes.

2. In a friction shock absorber, the combination with a friction casing; of a; plurality of friction shoes slidingly telescoped within the casing; a spring follower ring in wedging engagement with said shoes; .a spring within the casing yieldingly opposing inward'movement of-the shoes; a second spring within the casing buttressed against said spring follower ring for yieldingly opposing inward movement of the latter; and a pressure'transmitting member extending through said spring follower ring and bearing at opposite ends on said shoes and first named spring for transmitting pressure from the latter to said shoes. v

3. In a friction shock absorber, the combination with a friction casing; of a plurality of friction shoes slidingly telescoped within the casing; a sprin follower in wedging engagement with said shoes, said spring follower having a' central bore; a plunger slidable in said bore, said plunger being in shouldered engagement with the shoes; spring means within the casing bearing on said plunger to yieldingly oppose inward movement of the latter; and additional spring means within said casing bearing on said spring follower for yieldingly opposing inward movement of the latter.

4. In a friction shock absorber, the combination with a friction casing; of a plurality of friction shoes slidingly telescoped within the casing; a spring follower ring; cooperating wedge faces on said ring and shoes; a spring within the casing bearing'on said ring to oppose inward movement'of the latter; a plunger extending through s'aidring and buttressed at its outer end against said shoes; and a second spring bearing on said plunger to oppose inward movement of the latter.

5. In a friction shock absorber, the combination with a friction casing; of a plurality of friction shoes slidingly telescoped within said casing, said shoes having laterally inwardly projecting flanges thereon at their outer ends; a follower ring in wedging engagement with said shoes; a plunger slidable in said ring and hearing at its outer end on the flanges of said shoes; a spring within the casing bearing on said plunger and'yieldingly opposing inward movement of the same; and a, second spring within the easing bearing on said follower ring and yieldingly opposing inward movement of the same.

GEORGE E. DATI-I.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,002,498 Symington Sept. 26, 1911 1,941,787 Clark Jan. 2, 1934 2,156,779 Duryea -May 2, 1939 2,159,457 Sproul May 23, 1939 2,417,410 Gray Mar. 18, 1947 

